[CMake] Change hardcoded 'lib' and 'bin' in CMakeLists.txt to 'LIB_INSTALL_DIR' and...

[CMake] Change hardcoded 'lib' and 'bin' in CMakeLists.txt to 'LIB_INSTALL_DIR' and 'EXEC_INSTALL_DIR'.
https://bugs.webkit.org/show_bug.cgi?id=97419

Patch by Byungwoo Lee <bw80.lee@samsung.com> on 2012-09-24
Reviewed by Gyuyoung Kim.

Use the value of LIB_INSTALL_DIR and EXEC_INSTALL_DIR instead of
hardcoding 'lib' and 'bin' for CMAKE_{ARCHIVE,LIBRARY,RUNTIME}_OUTPUT_DIRECTORY.

* CMakeLists.txt:
Use ${LIB_INSTALL_DIR} instead of hardcoding "lib".
Use ${EXEC_INSTALL_DIR} instead of hardcoding "bin".

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@129447 268f45cc-cd09-0410-ab3c-d52691b4dbfc